Sheathed electrical conductor



O. A. FREDERICKSON SHEATHED ELECTRICAL CONDUCTOR Filed Feb. 25, 1926 Sept. l0, 1929.

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ATTORNEY UNITED STATES PATENTy OFFICE.

oT'ro A. rREnERTcxsoN, wmEMoLn COMPANY,

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OF WETHERSFIELD, CONNECTICUT, .ASSIGNOR TO THE OF HARTFORD, CONNECTICUT, A CORPORATION OF CON- SHEATHED ELECTRICAL CONDUCTOR.

.Application led February 25, 1926. Serial No. 90,649.

This invention relates to insulating tubes or conduits for Aprotecting electrical wires such as are used in wiring buildings to supply current for lighting and other purposes.

It is highly important that wires or electrical conductors such as are used in wiring buildings be well insulated electrically and also well protected against mechanical injury. It is also important that the protecting casing be capable of withstanding a strong pull in the direction of its lengt In order to secure the required electrical insulation and mechanical protection it has been customary heretofore to place about a 16 wire conductor a number of successive sheaths or layers of protecting material, but this necessitates a number of different operations each of which adds to the cost of the final product in material and labor, and even when 20 the protecting sheaths provided heretofore afford the desired electrical insulation and the desired degree of protection against mechanical injury, they may not afford the de-a sired tensile strength to withstand the strong pulling forces to which they may be subjected during installation.

Having the above matters in mind the preshaving a stron durable construction that affords good mec anical protection for the conductor it'encloses and which also possesses good insulating properties, while at the same time it is constructed of inexpensive material and is easy and inexpensive to manufacture.

The primary feature of the present invention resides in a conduit comprising a woven tube formed of large, hard warp threads made of paper and which are tightly interwoven with small strong weft threads, the construction being such that the warp threads lie side .by side in close relation to each other about the enclosed conductor to form a strong, durable protecting casing having hard thick walls.

In weaving the tube of the present invention the small strong weft threads are preferably sunk into the surface of the large paper warp threads so that the weft threads lying between adjacent warp threads will not through the conduit of Fig. l;

space the latter apart an appreciable distance, and as a result a tight protecting tube is formed which may be readily treated with a water proofing material to' render the tube moisture proof. The warp threads preferably are not displaced appreciably from their straight line position by the weft threads, and as a result the conduit of the present invention is well adapted to wit-hstand a strong pull in the direction of its length Without stretching appreciably.

A further advantage of a conduit constructed in accord ance with the present invention resides inthe fact that it is easy to weave on a circular loom, since the small strong weft threads are readily carried by the traveling shuttles while the large warp threads may be led to the weaving point from as large a source of supply as desired. f

The construction of the conduit of the present invention will be best understood from the following description when read in connection with the. accompanying drawings showing one good practical form thereof.

In the drawings Fig. l is a perspective view of a conduit y constructed in accordance with the present ent invention relates to a iiexible conduit' invention;

Fig. 2 is a longitudinal sectional view Fig. 3 is a transverse conduit; and

Fig. 4 is an elevation of one of the warp threads.

The conduit forming the subject matter of the present invention may be woven about an insulated wire as the conduit is formed, or if desired the insulated wire may be introduced into the conduit after the latter is completed and the conduit may be constructed to enclose a single wire l0 which is protected by rubber or other insulating material 11, as shown, or it may be employed to protect two or more conductors.

The warp threads l2 employed in constructing the conduit of the present invention are preferably formed of. thin strips of paper 13 that are tightly twisted to form relatively large hard strands which may be treated with l100 sectional view of the hardening or fire-proofing material before they are woven into the tu e.

The weft threads 14: are preferably formed of relatively small strong strands that` may be made of cotton, and theyT extend spirally about the conduit as shown, passing alternately under and over the warp threads 12. -The warp threads 12 are maintained under suiicient tension during their weaving operation to hold them straight so that the weft threads 14: areA caused to curve around the warp threads, and the weft threads are sunk into the surface of the aper warp threads as shown so that they will threads apart an appreciable amount. The tension of the weft threads will serve to some extent to force them into the surface of the warp threads, but this may be further accomplished by exerting pressure upon the outer wall of the conduit.

The construction of the conduit is preferably such that the warp threads 12 lie in close parallel relation to each other as shown and are rmlysecured in place by the weft threads 14. In this manner a conduit is produced which is vinexpensive to manufacture and which has thick tough walls that aiord good mechanical and electrical protection, and since the large strong warp threads extend lengthwise of the conductor the tensile strength of the conduit in the direction of its length is exceptionally high. If desired the conduit may be treated with water-proofing and ire-proong materials to increase its protective qualities.

What is claimed is:

A tubular fabric conduit for electrical conductors, comprising a tough, light-weight woven tube formed of relatively large, hard strands of twisted paper that extend lon itudinally of the tube in straight parallel re ation to the axis of the tube with their adjacent edges contacting, and small strong weft threads interwoven with the larger warp strands and looped about and sunk into the surface of the straight warp strands to pass between them andbind the warp strands together so that their edges contact throughout practically their entire length to form a protecting tube having a thick, tough wall that possesses exceptionally high tensile strength and which due Ato the straight condition of the warp strands will not stretch appreciably under longitudinal tension.

In. testimony whereof, I have signed my y name to this specification.

o'rTo A. FREDERIcKsoN.

not space the warp l 

